Embodiments of the inventive concept relate to memory systems and memory controllers. Embodiments of the inventive concept relate to methods of operating a memory controller that control the definition or shaping of a data pattern.
A non-volatile memory device, such as a NAND flash memory device, includes a great number of memory cells. With increased integration density made possible by emerging fabrication technologies, the separation distance between adjacent (and nearby) memory cells has decreased markedly. The increasingly close proximity of individual memory cells, together with other systemic and functional considerations, cause certain problems related to the reliability of stored data.
One important functional consideration related to data reliability in emerging non-volatile memory devices is the pattern with which data is stored across an array of proximate memory cells. Poorly defined (or undesirable) data programming patterns can lead to data degradation, whereas more appropriately defined data programming patterns result in better data reliability. For instance, during programming of a “target memory cell” selected during a programming operation, data previously stored in adjacent or proximate memory cells may be unintentionally disturbed (i.e., erroneously changed) due to certain coupling effects (e.g., electric field coupling or F-poly coupling). That is, coupling effects may change (e.g., widened) the threshold voltage distribution of proximate memory cells and adversely affect the reliability of the non-volatile memory device. Therefore, methods of enhancing the reliability of the non-volatile memory device are desired.